Influenza: the reemergence of an ancient disease and its risk of pandemia

Influenza is a seasonally, acute respiratory disease, highly transmissible. The diversity of the natural reservoirs of influenza A virus and its faculty of reassortment increase the risk of a new pandemia. Prevention strategies during the outbreaks include vaccination indicated to risk population as infants between 6 to 2 years old, persons above 65 years old, pregnant women and patients with underlying diseases. Antiviral prophylaxis is useful to control small outbreaks and to be used in household contacts of risk population who have not been vaccinated. Antiviral drugs as a treatment should be considered in persons with severe disease. During a pandemia these prevention measures must be reinforced and rational use of antiviral drugs and vaccine with the pandemic strain should be emphasized.     

Post-recurrence survival in hepatocellular carcinoma after percutaneous radiofrequency ablation

Background

Overall survival in hepatocellular carcinoma patients treated with percutaneous radiofrequency ablation is influenced by both recurrence and successive treatments. We investigated post-recurrence survival after radiofrequency ablation.

Methods

Data on 103 early/intermediate patients initially treated with radiofrequency ablation and followed for a median of 78 months (range 68–82) were retrospectively analysed. If intrahepatic disease recurrence occurred within or contiguous to the previously treated area it was defined as local, otherwise as distant; recurrence classified as Barcelona Clinic Liver Cancer stage C was defined by neoplastic portal vein thrombosis or metastases.

Results

A total of 103 patients were included (82.5% male; median age 70 years, range 39–86). During follow-up, 64 recurrences were observed. Median overall survival was 62 months (95% confidence interval: 54–78) and survival rates were 97%, 65% and 52% at 1, 4 and 5 years, respectively. Median post-recurrence survival was 22 months (95% confidence interval: 16–35). Child–Pugh score, performance status, sum of tumour diameters at recurrence and recurrence patterns were independent predictors of post-recurrence survival.

Conclusions

In patients with hepatocellular carcinoma after radiofrequency ablation, clinical and tumour parameters assessed at relapse, in particular the type of recurrence pattern, influence post-recurrence survival.     

uPA‐uPAR molecular complex is involved in cell signaling during neuronal migration and neuritogenesis

Background: In the development of the central nervous system (CNS), neuronal migration and neuritogenesis are crucial processes for establishing functional neural circuits. This relies on the regulation exerted by several signaling molecules, which play important roles in axonal growth and guidance. The urokinase‐type plasminogen activator (uPA)—in association with its receptor—triggers extracellular matrix proteolysis and other cellular processes through the activation of intracellular signaling pathways. Even though the uPA‐uPAR complex is well characterized in nonneuronal systems, little is known about its signaling role during CNS development. Results : In response to uPA, neuronal migration and neuritogenesis are promoted in a dose‐dependent manner. After stimulation, uPAR interacts with α₅‐ and β₁‐integrin subunits, which may constitute an αβ‐heterodimer that acts as a uPA‐uPAR coreceptor favoring the activation of multiple kinases. This interaction may be responsible for the uPA‐promoted phosphorylation of focal adhesion kinase (FAK) and its relocation toward growth cones, triggering cytoskeletal reorganization which, in turn, induces morphological changes related to neuronal migration and neuritogenesis. Conclusions : uPA has a key role during CNS development. In association with its receptor, it orchestrates both proteolytic and nonproteolytic events that govern the proper formation of neural networks. Developmental Dynamics 243:676–689, 2014. © 2014 Wiley Periodicals, Inc.     

High degree of Plasmodium vivax diversity in the Peruvian Amazon demonstrated by tandem repeat polymorphism analysis

Molecular tools to distinguish strains of Plasmodium vivax are important for studying the epidemiology of malaria transmission. Two sets of markers-tandem repeat (TR) polymorphisms and MSP3α-were used to study Plasmodium vivax in patients in the Peruvian Amazon region of Iquitos. Of 110 patients, 90 distinct haplotypes were distinguished using 9 TR markers. An MSP3α polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using HhaI and AluI revealed 8 and 9 profiles, respectively, and 36 profiles when analyzed in combination. Combining TR and PCR-RFLP markers, 101 distinct molecular profiles were distinguished among these 110 patients. Nine TR markers arrayed along a 100 kB stretch of a P. vivax chromosome containing the gene for circumsporozoite protein showed non-linear linkage disequilibrium (I(SA) = 0.03, P = 0.001). These findings demonstrate the potential use of TR markers for molecular epidemiology studies.